Molecular imprinting processes widely occur in complex biosystems, thus, selective and specific biological moieties bound by antibodies, such as hormones, are vital for basic cell-cell communication. Experimental simulation of cell imprinting has been predominately developed using bulk polymerizations in which guests, or templates, are used to create a molecular “impression” via incorporation within the infrastructure of appropriately juxtaposed ionic, hydrogen bonding, or other non-covalent loci. Small organic guests are typically used as the template from which, after its removal, the cavity, shape, and binding site's directivity of the host are frozen in orientation for subsequent re-recognition of structurally related guests. There has been developed a novel monomolecular imprinting process, whereby porphyrin-cored dendrimers possessing terminal alkenes were initially created, followed by alkene cross linking to give the host-guest combination; porphyrin removal thus created the desired cavity possessing the desired recognition sites. Such host-guest molecular recognition generally relies on intermolecular assembly of components.
Based on previous work concerning the hexameric self-assembly of meta-bis(terpyridinyl)arenes possessing the critical 120° angle with respect to the two ligating moieties, it was noted that the Fe(II) hexamer is sensitive to basic conditions compared to the more robust Ru(II) analogue; thus under basic conditions, demetallation quantitatively regenerated the starting bis-ligand. It has similarly been shown that the related tpy2Cu complex can also be destroyed by KCN. Such a facile disassembly process coupled with the high yield hexamer macrocyclization suggests the possibly of reversible assembly in an appropriate molecular nanotemplate.
Thus there exits a need to provide a method of molecular nanofabrication wherein the self-assembly process occurs by an intramolecular mechanism in which a macromolecular skeleton possesses multiple ligands capable of reversible assembly-disassembly triggered by the presence of metal ions.